Technical Field
The present disclosure generally relates to a picking-up and placing process for devices and device module, in particular, to a picking-up and placing process for electronic devices and an electronic module.
Description of Related Art
Inorganic light emitting diodes (LEDs) have features of self-luminous, high brightness and so on, and therefore have been widely applied in the fields of illumination, displays, projectors and so forth. Taking monolithic full color micro-LED displays as an example, monolithic micro-displays have been widely used in projectors and faced with a bottleneck of colorizing technology. Generally, in order to obtain different colored lights, epitaxial processes for fabricating a single LED chip including a plurality of light emitting layers capable of emitting different colored lights has already been proposed. Therefore, the single LED chip can provide different colored lights. Since lattice constants of the light emitting layers capable of emitting different colored lights are different, it is difficult to grow such light emitting layers on a same substrate. In addition, another colorizing technology using a LED chip accompanied with different colored wavelength conversion materials has been proposed, wherein the color wavelength conversion materials are excited by the lights emitted from the LED chip and generate the excited lights of different colors. However, the conversion efficiency of the wavelength conversion materials is low and it is difficult to coat the wavelength conversion materials uniformly.
Expect the above two technologies providing different colored lights, a picking-up and placement technique for LED chips is proposed because the LED chips capable of emitting different colored lights may be respectively formed on different substrates to have better epitaxial quality and luminous efficiency. Therefore, the picking-up and placement technique for the LED chips has a better chance to enhance brightness and display quality of a monolithic micro-display significantly. To one ordinary skilled in the art, how to efficiently pick-up and place the LED chips on a circuit substrate of the monolithic micro-display is an important issue. In addition, due to the size of the LED chip is by the microminiaturization, how to make the micro LED capable of emitting light with better collimation is an another important issue.